That familiar feeling comes from deep in the brain

When you see a familiar face in the crowd, thank your perirhinal cortex. A new study shows how changing the activity in this brain area can make the new seem old, and the old seem new again. It’s happened to all of us at one time or another: You’re walking through a crowd, and suddenly a face seems incredibly familiar — so much so that you do a double-take. Who is that? How do you know them? You have no idea, but something about their face nags at you. You know you’ve seen it before. The reason you know that face is in part because of your perirhinal cortex. This is an area of the brain that helps us to determine familiarity, or whether we have seen an object before.…